Using a esim overseas?

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bun1

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#325060 3-Jul-2026 12:57

I am a complete novice in this space. I am travelling to UK/Ireland/France via Singapore in October and want to know about esims.
I definitely do not want to get hit with roaming charges. What is the best way to go about this? We are stopping off in Singapore for a couple of days on the way over and in Perth for a couple of days on the way back.
Should I just get a worldwide one or be better off getting a europe one and just relying on wifi for the couple of days at either end?
Also what happens if someone needs to contact my NZ number?

What sort of costs am I looking at?

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#3508350 3-Jul-2026 13:34

Which provider are you with? To make your nz number still available there is a way to use wifi-calling over a secondary e-sim data connection.

For your short stints weigh up the cost of daily roaming with your provider vs buying a travel esim that covers multiple locations or one for each location in succession.

For travel e-sims try to find who the provider is before buying, location matters for latency e.g. buying a e-sim whos provider is in poland when you’re physically in singapore will make it quite slow.

noroad

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#3508354 3-Jul-2026 13:59

I use https://www.airalo.com/ problem solved. In-fact use my referral code for a discount if you so desire "TONY4571"

invisibleman18

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#3508366 3-Jul-2026 15:35

I used this one last year on a similar trip (UK, Ireland, France and Switzerland):

https://simcorner.com/products/esim-europe-unlimited-data

Worked perfectly and had strong signal everywhere. It was only a data package as didn't need to make any calls over a network so I turned my NZ sim off in the sim settings to make sure I didn't in advertently get any roaming charges. Recommend this one if you only want data. Think we got it when there was a decent sale.

timmmay

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#3508441 3-Jul-2026 19:51

I also use Airalo. Turn up in the country, jump on the app with WiFi, buy an eSim for the time you need with just data, with a phone number, etc. You can keep your NZ number active but tell your phone to use the other eSim for everything, and you could redirect your NZ number to voicemail if you wanted to avoid incoming roaming charges.

I was in Australia when my 2degrees SIM roaming failed, and my family was in a different location from me. I jumped on WiFi somewhere and grabbed an Airalo eSim for maybe $15 for data only that lasted the last few days of our trip. 2degrees started working a few hours later.

tchart

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#3508444 3-Jul-2026 20:32

noroad:

I use https://www.airalo.com/ problem solved. In-fact use my referral code for a discount if you so desire "TONY4571"

+1 used Airlo in the US in March for 3 weeks. Was great and much cheaper than the $8 a day 2 degrees want.

alinz

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#3508448 3-Jul-2026 21:44

If you can get by with 10gb or less, I think a global one probably makes the most sense with the countries you're visiting.

I personally use eSIMDB (set currency to NZD, apply promo codes and use the filters).

Make sure to enable data roaming for the esim.

If your phone is a Samsung or an iPhone, and your network is One or 2degrees; you can keep your local number working over the data of the esim without roaming charges (It won't work on Spark).

Set your local sim to 'manual network selection' before leaving NZ.

Additionally on a Samsung, you'll need to enable these two settings.

It may or may not work on other brands, I haven't tested.

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mentalinc

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#3508886 6-Jul-2026 08:28

alinz:

you can keep your local number working over the data of the esim without roaming charges (It won't work on Spark).

Do we know why it doesn't work for Spark? is there another setting missing or is it their backend doesn't support wifi calling properly?

I assume the wifi calling version works based on tests in NZ in airplane mode, its just the e-sim data version that is not working?

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frankv

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#3508893 6-Jul-2026 08:48

Beware that some esims are country-dependent. I used IIRC holafly (sorry, I'm not 100% sure which provider. I know this isn't as helpful as it could be) on a trip to Europe in 2024. Although it worked just fine in other countries, it was tied to France so I couldn't buy more data when I wasn't in France. Of course, I only discovered this when I had left France and wasn't returning there.

It's much cheaper to get data only, but if you're using AirBnB or similar you may still need a phone number to be able to receive texts relating to your accommodation, or to make calls.

As others have said, counterintuitively you need to turn on data roaming when using an esim. Turning on data roaming doesn't turn on roaming on your NZ SIM.

alasta

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#3508927 6-Jul-2026 10:39

mentalinc:

alinz:

you can keep your local number working over the data of the esim without roaming charges (It won't work on Spark).

Do we know why it doesn't work for Spark? is there another setting missing or is it their backend doesn't support wifi calling properly?

I assume the wifi calling version works based on tests in NZ in airplane mode, its just the e-sim data version that is not working?

I imagine it's probably because Spark only allows wifi calling within New Zealand.

mentalinc

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#3508932 6-Jul-2026 10:59

How does Spark know if you're in New Zealand if you're in Airplane mode?

Would using a VPN back to NZ get "around" the 'within New Zealand' issue?

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SpartanVXL

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#3508937 6-Jul-2026 11:35

mentalinc:

How does Spark know if you're in New Zealand if you're in Airplane mode?

Would using a VPN back to NZ get "around" the 'within New Zealand' issue?

Can’t do this on phone, wifi-calling bypasses vpn on device. You’d have to connect to actual wifi with vpn gateway back.

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KiwiSurfer

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#3508938 6-Jul-2026 11:38

frankv:

As others have said, counterintuitively you need to turn on data roaming when using an esim.

Frequently this is because the eSIM is not actually from a mobile operator in that country. As mentioned in this thread Poland operators (and a number of other 'interesting' countries) are behind a lot of the eSIMs. So you'll get an "Australian" eSIM which is technically a Polish eSIM set up with roaming only allowed to Australian operators. This makes for some interesting routing which can affect data performance etc.

Generally, I go for the following rules when travelling:-

A couple of days? Just roam with NZ SIM. I'm with One NZ who have excellent 5G/4G roaming across multiple operators almost everywhere I go. But even 2deg/Spark are pretty good too even if limited to 3G/4G in many cases.
Up to a week in the same country? Get local SIM on arrival from one of the major names. E.g. Australia I just get the a SIM from the Vodafone AU shop in the airport. I get full speed 5G data and often the airport store has travel deals specific to airport stores. And nicest thing is data traffic takes the direct route back to NZ and not via e.g. Poland.
Multiple countries? I'll do my research and see if there is a mobile operator in the first country I visit that has good roaming to neighbouring countries. For EU trips this is pretty easy due to the EU rules. Asia is pretty good too, I had a Singapore SIM that worked in several other Asian countries so I had a cheap Singapore SIM on Day 1 which I used for 2 weeks in Malaysia and Thailand with no issues. Failing that eSIM would be my last resort.
Stopovers? If its <24hrs I'll just roam. Yes it is $10 a day but it'd cost more than that of my time faffing around with eSIMs so why bother. Plus <24 hours means you're more likely to need things to just work to manage airline apps, make contact with family, etc. (Although if you have a foreign SIM already sometimes the roaming deals are better compared to NZ so can always try that).

noroad

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#3508940 6-Jul-2026 11:46

mentalinc:

How does Spark know if you're in New Zealand if you're in Airplane mode?

Would using a VPN back to NZ get "around" the 'within New Zealand' issue?

The voice over IP server (VoWIFI) generally has a whitelist of approximate NZ IP's (this can be fairly accurately determined by the Internet routing table). Yes, if you VPN back to an NZ based VPN host you can potentially bypass this block. Obviously they don't want you to do this as they make more money if you make international calls.

noroad

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#3508942 6-Jul-2026 11:48

noroad:

The voice over IP server (VoWIFI) generally has a whitelist of approximate NZ IP's (this can be fairly accurately determined by the Internet routing table). Y

To be fair however, opening up a voip server to the entire internet is a security nightmare I would never allow myself.

pdh

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#3509024 6-Jul-2026 17:58

I'm on Skinny and wife is on One - both with dual-sim Samsung Ultras (S23U & S24U).

We're heading off in August for 53 days on a road trip in Europe (London and 12 countries on the continent) from France to Sweden to Greece.

My plan is to buy Orange 30 day esims for us each - 50 GB data & unlimited txt/calls for 39 GBP - and renew them once.
These should give us each a French 'real' number for AirBnB's & random calls.
I can get the esims online - and fix the numbers - then they activate when we hit the ground in London.

I'll keep the NZ Sims in the phones - allowing incoming SMS (for 2FA) but ignoring incoming Voice calls from NZ.
We will both disable VoiceMail on the NZ services.
And set the Orange SIM to default for data, calls & messages.
And toggle 'off' Data Switching to avoid pinging Skinny / One if Orange drops data at some point.

This should give us the Holy Grail of full comms in Europe - with no loss of 2FA.
Except for some countries with whom NZ doesn't do SMS (Poland, Slovakia, Romania & Bulgaria ?)
Relying on WiFi calling is out - as our travelling will be in a car (no train stations/airports with free WiFi !).
Total cost is 156 GBP (365 $NZ) for both phones for 8 weeks - about 3.40 $ a day each.

Can anyone see flaws - or improvements ?

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